Methods for carrier synchronization of short packet turbo coded signals

Turbo codes, which provide superior performance, close to the Shannon limit, have found their way into WLAN and mobile system standards. Synchronization of turbo-coded signals operating at low SNR conditions may be difficult, especially for short packet transmission. This paper proposes two techniques for using the turbo decoder information to improve the carrier phase and frequency offset synchronization for short packets communication systems. One of those techniques, which are based on soft-decisions produced by the Turbo decoder, can be used for tracking. The other technique is based on maximizing a newly invented cost function, the MSSO (Δf,Φ) function, to acquire and track the carrier frequency and phase errors, with the cost of complexity. A combination of the two techniques is introduced as well to provide a wholesome solution.